In recent years, well known as a technology to eject the droplets of the liquid solution onto an object material, is a so-called electrostatic liquid solution ejecting technology which electrically charges the liquid solution in a nozzle, and generates an electrical field between the object material and the nozzle, after which the droplets of the charged liquid solution are ejected from the top end of the nozzle onto the object material. The electrostatic liquid solution ejecting technology of interest applies ink or electrically conductive paste as the liquid solution to be ejected, and which is preferably used for placing minute dots to form high quality images on a recording medium, or which is preferably used for forming an ultra-fine wiring pattern on a circuit plate.
Typically, a regular liquid ejecting apparatus (a head to eject the liquid) to eject the electrically conductive liquid solution allows the nozzle to project slightly from a supporting member (such as a nozzle plate), and uses an electrical field concentrating function at the top of the protruded nozzle. Accordingly, the nozzle is a very important section for the liquid solution ejecting performance. As an example of this nozzle, Patent Document 1 discloses nozzle 15 which is formed of silicon oxide, and projects about 10-400 μm, while Patent Document 2 discloses an isosceles triangle shaped nozzle (which is ink ejecting section 16), formed by a cutting operation.
[Patent Document 1] Unexamined Japanese Patent Application Publication No. 2003-311,944 (see paragraph 0035, and FIG. 3)
[Patent Document 2] Unexamined Japanese Patent Application Publication No. 2003-39,682 (see paragraph 0014, and FIG. 1)
However, in the above-described liquid ejecting apparatus using a method in which the electrical field is concentrated to the top of the nozzle, due to the nozzle protruded from the supporting member of the nozzle, it is very difficult for a wiping operation (which means to wipe the surface of the nozzles by a rubber blade and the like) for the cleaning, which is an important factor for stable ejecting action of the liquid solution, and thereby a major maintenance problem results, in addition, the ejecting performance may be reduced.